Hydrogenation catalyst and process



HYDRQGENATEGN t'JATALYdT AND PROCESS Philip A. Lefrancois, Cranford, Joseph F. McMahon,

liselin, and Ernest Solomon, Montclair, N31, assignors,

by means assignments, to Pullman incorporated, a corporation of Delaware No Drawing. Filed Aug. 20, 1959, Ser. No. 834318 1 Claim. ((31. 208-111) This invention relates to a hydrocarbon conversion process involving hydrogen transfer reactions. In one aspect this invention relates to an improved type of catalyst particularly useful for effecting hydrogen transfer reactions and to a method of preparation of such catalyst. In another aspect this invention relates to a process for altering the hydrogen-carbon ratio of a single unsaturated hydrocarbon or mixture of unsaturated hydrocarbons by hydrogenation in the presence of a particular catalyst. In another aspect this invention relates to an improved hydrogenation-hydrocracking process efiected in the process of a particular catalyst.

Various types of hydrogen transfer reactions are known to the art including hydrogenation, and hydrocracking or destructive hydrogenation. The treatment of hydrocarbons with hydrogen in the presence of a hydrogenation catalyst is well known in the art. With some exceptions the desirability of liquid fuels and lubricants is roughly proportional to the combined hydrogen that each contains. With the exception of cracked products, however, many petroleum fractions contain little or none of the easily hydrogenated olefinic groups so that deep-seated chemical changes are necessary to promote the entrance of hydrogen atoms into the molecule. High grade kerosenes are made-up of saturated hydrocarbons, parafiins and naphthenes and are low in sulfur, nitrogen and oxygen compounds. However, kerosene distiliates from most crudes usually possess few or none of these characteristics. By hydrogenation, aromatics of such kerosene distillates can be converted to naphthenes, any of the parafiins present are saturated while sulfur, nitrogen and other extraneous elements are substantially removed as hydrogen sulfide, ammonia, etc.

by the cracking and reduction of corresponding compounds.

The hydrogenation of aromatic hydrocarbons whether they are substantially the only components of the charge stock or are present as components of a hydrocarbon fraction, is relatively diflicult to effect. With presently used catalysts, a relatively severe combination of con ditions must be applied even with catalysts of high activity. Under such severe conditions the selectivity of catalysts decreases due to concomitant reactions such as hydrocracking. This latter reaction is especially undesirable When it is desired to upgrade a hydrocarbon fraction Without substantial change in boiling point, or when it is desired to produce high yields of relatively pure petro-chemicals since it leads to loss of yield of the desired product and makes the process more difiicult to control to obtain the desired results.

On the other hand hydrocracking, or destructive hydrogenation, is a process whereby a hydrocarbon fraction is decomposed or cracked to some extent, as well as hydrogenated, in order to make lower boiling products such as, for example, gasoline. It differs from hyported on either alumina or silica.

dflhhflidfi Fatented Feb. 9, 1965 drogenation in that a change in boiling range of a given hydrocarbon fraction is not usually desired in hydrogenation. In addition, hydrocracking is usually effected at a higher temperature and other more severe conditions than normally employed during hydrogenation.

The destructive hydrogenation, hydrocracking or hydrogenolysis of heavy residual hydrocarbon stocks such as reduced crude, vacuum reduced crude, topped crude cracking residium and like stocks has been known for some time. Useful products, which can be recovered from such a process, include hydrogenated hydrocarbons in the boiling range of gasoline, diesel oil, cycle oil, fuel oil and light gas oil.

Usually, the gasoline boiling range materials are not of exceptional quality and must be subjected to further treatment such as reforming, to provide a good grade of gasoline. Numerous other difllculties have been commonly encountered in the prior art hydrocracking processes, which usually include short catalyst life resulting from excessive carbon deposits on the catalyst surface, low conversion to desired product per pass, and excessive gas formation. in addition, prior art catalysts are susceptible to deactivation by suiiur and other contaminants which are usually present in the feeds employed in hydrocracking processes.

An object of this invention is to provide an improved type of catalyst particularly useful for effecting hydrogen transfer reactions.

Another object of this invention is to provide an improved process for the hydrogenation of aromatic hydrocarbons in good yield and selectivity.

Another object of this invention is to provide a process for hydrogenating a hydrocarbon fraction containing unsaturated hydrocarbons by contacting said fraction with an improved catalyst comprising a compound of molybdenum.

A further object is to provide a new and improved particular hydrogenation catalyst comprising a compound of molybdenum which catalyst is sulfur insensitive and possesses high hydrogenation activity and good thermal stability.

A further object of this invention is to provide an improved hydrocracking process efiected in the presence of a particular catalyst of high hydrogenation activity.

It is a further object to provide a method for the preparation of catalysts having the above characteristics.

Various other objects and advantages of this invention will become apparent to those skilled in the art from the accompanying description and disclosure.

The above objects are accomplished by providing a catalyst comprising an oxide and/or sulfide of molybdenum and of nickel supported on a silica/alumina support having an alumina content of between about 10 and about 50 Weight percent based on the weight of the support. It has been found that the catalysts of this invention possess improved hydrogenation activity as compared with the activity of corresponding catalysts in which an oxide and/or sulfide of cobalt is used in place of the nickel compound, and also possess improved hydrogenation activity as compared with catalysts containing an oxide and/or sulfide oi molybdenum and nickel sup- It also has been found that the catalysts of this invention are particu- '10 and about 30 weight percent alumina.

Q larly useful as hydrocracking catalysts-under appropriate operating conditions.

The content of molybdenum compound (calculated as molybdenum trioxide) in the finished catalyst composite may range between about 3 and about 30 weight percent based on the total weight of the catalyst, and within this range, the concentration of the oxide and/or sulfide of nickel is such to provide an atomic ratio of molybdenum to nickel of between about 1 and about 5. For example, at a concentration of the molybdenum compound within the aforesaid range, the nickel compound is present in an amount between about 0.24 and about 12.2 weight percent (calculated as nickel) based on the total weight of the catalyst. It has been found, however, that superior hydrogenation activity is exhibited by the catalysts in which the oxide and/ or sulfide of molybdenum is present in an amount between about 6 and about 20 weight percent at an atomic ratio of molybdenum to nickel of between about 1 and about 3, particularly between about 2 and about 3. The optimum concentration of metal compounds depends to a large extent upon the particular support employed, i.e. on the alumina content of the silica/alumina support, and on the particular reaction to be effected.

Although the support employed for the catalysts of this invention may contain alumina in an amount between about 10 and about 50 weight percent based on the total weight of the support, the preferred catalysts are prepared from silica/alumina supports containing between about Within an alumina content of between about 10 and about weight percent, optimum activity is observed at a concentration of molybdenum compound of between about 6 and about 12 weight percent, for example, about 8 weight percent, particularly at an atomic ratio of molybdenum to nickel of between about 2 to about 3. On the other hand, when the alumina content is higher, e.g. between about 15 and about 30 Weight percent, the optimum content of the molybdenum compound is between about 10 and about weight percent at an atomic ratio of molybdenum to nickel of between about 1 and about 3, particularly between about 2 and about 3.

For the purpose of this invention the support containing between about 10 and about 15 weight percent alumina is referred to herein as the low alumina support, and the support containing higher alumina contents, e.g. between about 15 and about 30 weight percent or higher, is referred to herein as the high alumina support. This distinction is made since in certain respects, to be more fully discussed hereinafter, catalysts prepared from the low and high alumina supports do not possess the same characteristics or properties.

An alumina content of between about 10 and about 15 weight percent, based on the weight of the support, corresponds to between about 8 and about 14, based on the total weight of the catalyst. Similarly, an alumina content of between about 15 and about 30 weight percent, based on the weight of the support corresponds to between about 11 and about weight percent, based on the total weight of the catalyst.

The silica/alumina support employed in accordance with the teachings of this invention may be prepared by methods well known to those skilled in the art. One method comprises coprecipitation of the oxides or hydrous oxides of aluminum and silicon from aqueous solutions of water soluble salts thereof. Thus, solutions containing appropriate proportions of the water soluble salts of aluminum, such as aluminum chloride, aluminum sulfate, aluminum nitrate and alkali metal aluminates such as sodium aluminate, and of silicon such as the alkali metal silicates, are treated with a basic precipitant, such as ammonium hydroxide, an alkali metal hydroxide or carbonate, or carbon dioxide or acid to precipitate a mixture of the hydrous oxides. The precipitate is then washed with water to remove water soluble impurities and then dried. Either the water washing or leaching process may be carried out both before and after the drying process. The primary drying operation may be effected at temperatures in the order of F. to 500 F. and then calcined at higher temperatures of between about 750 F. and about 1200 F. Another method comprises commingling an acid such as hydrochloric acid or sulfuric acid with commercial water glass (sodium silicate) under conditions to precipitate silica, washing with acidulated water or otherwise to remove sodium ions, commingling with an aluminum salt such as aluminum chloride and either adding a basic precipitant such as ammonium hydroxide to precipitate alumina, or forming the desired oxide by decomposition of the salt at an elevated temperature as the case permits.

The catalysts of this invention may be prepared by a variety of methods without departing from the scope of this invention. For example, one method comprises impregnating the alumina/silica support with the precursor compound of molybdenum, typical examples of which.

are silicornolybdic acid, phosphomolybdic acid and ammonium molybdate, followed by drying, if desired, and/or calcination at an elevated temperature. The calcined composite is then impregnated with the precursor compound of the nickel compound, typical examples of which are nickel. acetate, nickel chloride, nickel sulfate and nickel nitrate, followed by drying, if desired, and/ or calcination at an elevated temperature. The reverse order of addition of molybdenum and nickel also leads to active catalysts but generally, when the compounds are added successively, it is preferred to impregnate the silica/alumina support with the molybdenum compound prior to impregnation with the nickel compound. Alternatively, the intermediate calcination step may be omitted. The catalysts of this invention also may be prepared by coimpregnation of the alumina/ silica with the molybdenum and nickel precursor compounds. It is to be noted, however, that when co-impregnation is employed, the addition of ammonium hydroxide to the mixture to hold the two compounds in solution has been found to produce a catalyst of lower activity. When the co-impregnation technique is employed, a particularly active catalyst is produced by employing an aqueous solution of phosphomolybdic acid and nickel acetate.

When employed, the drying steps may be effected at a temperature of between about 100 F. and about 400 F. The intermediate calcination and/ or final calcination steps are effected at an elevated temperature such as between about 600 F. and about 1200 F. in the presence of air, nitrogen or other inert gases.

In accordance with a preferred embodiment of this invention, the calcined composite comprising the oxides of molybdenum and nickel is preconditioned with a gaseous stream comprising hydrogen sulfide, or the metal sulfide may be formed in situ such as, for example, when the feed stock to be treated contains a high sulfur content. When the catalysts are preconditioned by contacting with hydrogen sulfide, hydrogen is preferably employed as the carrier gas although other carrier gases such as nitrogen and argon may be employed. The concentration of hydrogen sulfide in the carrier gas may vary between about 0.1 and about 5 mole percent, preferably between about 1 and about 3 mole percent. The preconditioning or activation with hydrogen sulfide may be effected at a temperature between about 400 F. and about 1000 F. and at a pressure between about 50 and about 2000 pounds per square inch gage. As a result of sulfiding, the oxide of molybdenum is converted to a sulfide such as MoS or M08 or mixtures thereof, and the oxide of nickel is converted to a sulfide such as NiS or Ni s or mixtures thereof.

The above-described catalysts find particular utility in the hydrogenation of unsaturated hydrocarbons including olefinically and aromatically unsatured compounds.

The feed stock to be hydrogenated may consist of a single unsaturated compound such as when a high purity product is desired or it may comprise a mixture of such hydrocarbons. Thus, for example, aromatically unsaturated compounds such as benzene, toluene, naphthalene, styrene and derivatives thereof are suitable and typical reactants as well as aliphatically unsaturated compounds including acyclic and alicyclic compounds such as, for example, cyclohexene, cyclohexadiene, cyclopentadiene, methylcyclopentene, butenes, pentenes, heptenes, octenes, indene, etc., acetylenes, etc. and mixtures thereof. The process of this invention also may be used to reduce the degree of unsaturation of drying oils.

Also included within the scope of this invention is the hydrogenation of gasoline produced by a catalytic cracking process such gasoline usually being high in olefins, particularly monoolefins. The catalysts of this invention may also be employed to selectively hydrogenate any diolefins which may be present in catalytically cracked gasoline, to convert such diolefins to monoolefins in order to stabilize the gasoline against gum formation. Other feed stocks which may be hydrogenated by the catalysts of this invention are those in which the carbon to hydrogen ratio is high such as reduced crude oil and vacuum tower bottoms, i.e. hydrocarbon stock from which the light fractions have been removed. Hydrogenation of such residual oils increases the gravity thereof and tends to prevent excessive coke laydown during subsequent treatment thereof such as during a subsequent hydrocracking process. In addition, the feed stock may be a hydrocarbon fraction boiling within the range of about 325 F. to about 600 F. such as in particular a kerosene fraction containing unsaturated components. By hydrogenation, the aromatics contained in the petroleum fraction are converted to naphthenes, any of the olefins which may be present are saturated to form a hydrogenated product substantially free of unsaturated components and of improved smoke point. At the same time, sulfur, nitrogen and other extraneous elements which are usually present in the kerosene fraction or vacuum bottom feed stocks, for example, are substantially removed probably in the form of hydrogen sulfide, ammonia, etc.

In accordance with one embodiment of the process of this invention, a hydrocarbon or hydrocarbon fraction is contacted with the catalysts of this invention in the presence of added hydrogen under hydrogenation conditions with net consumption of hydrogen to cause selective hydrogenation of the feed components with minimum hydrocracking to produce product having a lower degree of unsaturation which, in the case of a hydrocarbon fraction boiling within the kerosene range, is evidenced by improvement in smoke point. The hydrogenation process of this invention may be conducted over a wide range of temperatures without departing from the scope of this invention. Such operating conditions include a temperature within the range of from about 200 F. and about 850 F, a pressure between about 0 pound per square inch gage (p.s.i.g.) and about 2000 p.s.ig. and a space velocity (defined as pounds of feed per hour per pound of catalyst) between about 0.1 and about 10.0. Generally speaking, the conditons within which optimum re sults are achieved, i.e. high hydrogenation activity and good selectivity, include a temperature of between about 400 F. and about 800 F., a pressure between about 200 and about 800 p.s.i.g. and a weight space velocity of between about 2 and about 10. Hydrogen should be intro duced into the reaction zone at a rate of from about 300 to about 20,000 standard cubic feet per barrel (s.c.f.b.) or the hydrogen to hydrogen mole ratio may fall within the range of from about 0.35 to about 50, preferably from about 1 to about 25 moles of hydrogen per mole of hydrocarbon with the total reaction pressure maintained between about 0 and about 2000 pounds per square inch gage (p.s.i.g.), preferably between about 200 and about 800 p.s.i.g. It is desirable that the hydrogen partial pressure be carefully controlled within the preferred range of from about 15 to about 1500 pounds per square inch absolute (p.s.i.a.) preferably from about to about 900 p.s.i.a. to elfect the desired conversion while maintaining the activity of the catalyst at a high level.

In accordance with another embodiment of the present invention, a higher boiling hydrocarbon fraction is converted to a lower boiling hydrocarbon fraction by hydrocracking or destructive hydrogenation. That is, in accordance with this embodiment, a hydrocarbon feed stock boiling within the kerosene boiling range and higher is hydrocracked in the presence of added hydrogen or a hydrogen-rich gas, such as re-cycle gas, etc., containing light (C -C hydrocarbons and under a pressure from about 200 to about 2000 pounds per square inch gage (p.s.i.g.) or higher in contact with the catalysts of this invention. In the hydrogenative cracking zone, or hydrocracking zone, conditions of operation are preferably maintained to favor hydrocracking of the charge without eifecting formation of low molecular weight gaseous compounds and little or practically no carbon production such that the process can be operated for comparatively long periods of time before necessitating periodic catalyst regeneration. These conditions include a pressure in the range of from about 200 to about 2000 p.s.i.g., temperatures from about 500 to about 1000 F. and a hydrocarbon space velocity of about 0.1 to about 10 pounds of oil per hour per pound of catalyst with hydrogen being added to the charge or reaction zone at the rate of about 1 to about 50 moles of hydrogen per mole of hydrocarbon feed. In the preferred operation, pressures of about 500 to about 1200 p.s.i.g. are employed, at temperatures of between about 600 F. and about 925 F., and a space velocity of about 0.5 to about 5 with hydrogen being added at rates of about 3 to about 12 moles per mole of hydrocarbon feed. Generally speaking, with any of the presently described catalysts, a less severe combination of temperatures and pressure conditions is employed when the catalysts are used to hydrogenate a feed stock without substantially changing its boiling point, as compared with the combination of operating conditions employed when hydrocracking or change in boiling point of the feed is desired.

Hydrocarbon feeds which may be effectively hydrocracked in the presence of the catalysts of this invention include distillate oils, gas oils, catalytic cracking cycle oils, residual and other heavy petroleum fractions, such as heavy gas oil, residuum from thermal or catalytic cracking processes, petroleum wax fractions, and reduced crudes in general. The term reduced crude as used herein is a crude oil from which the light materials and gasoline boiling range constituents have been removed, and which has then been distilled to remove the gas oils present. The initial boiling point of such an oil is usually about 675 F. to 700 F., although this may vary somewhat. Due to the high hydrogenation activity of the catalysts of this invention, the lower boiling fractions such as gasoline produced by hydrocracking of the heavier or higher boiling feeds, are low in olefins and thus do not necessarily have to be subjected to a subsequent hydrogenation treatment prior to use.

The catalysts of this invention are also useful for desulfurizing hydrocarbon oils, e.g. naphthas, kerosene, gasoline, gas oils, total crudes, etc. The desulfurization is effected at a temperature of about 600 F. to about 900 F., preferably about 650 F. to about 850 F. The desulfurization reactions can be effected at either exceptionally high pressures in the order of up to about 2000 p.s.i.g. or at pressures as low as 100 p.s.i.g. More usually, desulfurization by means of the catalysts of this invention is accomplished at a pressure of about 500 to about 1000 p.s.i.g. The desulfurization is effected in the presence of hydrogen and the conditions of operation are such that hydrogen is consumed in the operation. Generally, the hydrogen is supplied to the process at the rate of about 1000 to about 20,000 s.c.f.h., preferably at a rate of between about 3000 and about 10,000 s.c.f.b. Generally, the weight space velocity ranges between about 0.1 and about 15 pounds per hour of hydrocarbon feed charged to the desulfurization zone per pound of catalyst present therein, and more usually from about 3 to about 8. It is to be understood that hydrodesulfurization also may occur during the above-described hydrogenation or hydrocarcking processes.

The catalysts of this invention may be employed effectively as pellets, pills, spheres, rings, extrusions, lumps, granules, extrusions or in a powdered state and these forms may be used in both fluidized systems and those employing moving beds of contact material in either concurrent or countercurrent flow relative to the reactants. The catalysts may also be employed in a slurry type system without departing from the scope of this invention.

The following examples are offered as a better under- Catalysts I through V111 and Catalysts X111 through XV were prepared from the same fresh low alumina/ silica cracking catalysts containing 13 weight percent alumina and 87 weight percent silica. As may be seen from Table I, the molybdenum oxide concentration of Catalysts I through VIII ranged between about 3 and about 30 weight percent based on the total weight of the catalyst, the corresponding alumina content ranging between about 13 and about 9 weight percent, based on the total weight of the catalyst.

The support employed in the preparation of Catalysts IX through X11 was the same fresh high alurnina/ silica cracking catalyst containing 25 weight percent alumina and 75 weight percent silica. As may be seen from Table 1, the molybdenum oxide content ranged between about 3 and about 30 weight percent, the corresponding alumina content ranging between about 24 and about 16 weight percent, based on the total weight of the catalyst.

TABLE 1 Preparation of Catalysts LX V Composition 1 (weight percent based Weight Ammonium Dried at Nickel Acetate, Dried at on total weight of catalyst) Catalyst No. 01 M olybdatc, grams 250 F. grams in 1120 250 F. Support in 11 (00.) (hours) (00.) (hours) (grains) M00; NiO AhO; SiO;

,3 2 1 9s. as s. 70 75 20 g 1. 72 so 21 2 3. 02 0. s2 12. 52 84. s 1 46. 3G 3. 70 45 25. Q 1. 74 35 25 6. 04 1. 24 12. 06 80. 65 1 454. 50 46. 29 450 15.5 f 21. 91 500 19 7. 55 1. 55 11. 82 79. 07 1 43. 93 G. 17 45 26 g 2. 97 35 25. 5 3' 10.07 2.07 11. 42 70. 44 1 40. 90 9. 25 45 21. 5 4. 40 35 20 15. 3.10 10. 63 71.15 1 23.16 5. 51 35 16 7. 58 30 21. 5 15. 0 7. 79 10.04 07. 1 25.03 5. 51 35 18. 5 g 1. 51 30 23 o 15. 0 1. 5 10.85 72.6 1 31. 76 18. 51 45 22 2 9. 13 -15 22. 5 g 30. 2 6. 27 9. 0 00. 6 2 3 24. 09 0. 92 25. 5 a 0. 51 20 28. 5 I, 3.02 0. 63 2 1.1 72. 3 2 3 22. 73 2. 31 20 24. 5 m 1. 26 20 21. (i 7. 55 l. 55 22. 7 (18.2 2 3 20. 45 4. (33 20 24 '8 2. 51 20 23. 5 E, 15. 1 3. 1 20. 4 61. 4

U U E T; O Cobalt Acetate O percent alumina and 87 weight percent silica. percent alumina and 75 weight per-cont silica.

1 Calculated, based upon ingredients employed in preparing the catalyst.

standing of the present invention and are not to be construed as unnecessarily limiting thereto.

Catalysts I through X11 containing molybdenum oxide and nickel oxide, and Catalysts X111 through XV containing molybdenum oxide and cobalt oxide, on an alumina/ silica support, were prepared by the following general procedure: In each instance the alumina/silica support was impregnated with an aqueous solution of ammonium molybdate tetrahydrate (NH 3l\4O7O '4-H O. The impregnated support was then placed in an oven and dried at 250 F., and the dried composite was then ground to a powder and calcined at 1000 F. for 2 hours. In preparing Catalysts I through XlI the calcined material thus prepared was impregnated with an aqueous solution of nickel acetate tetrahydrate. In the preparation of Catalysts XIII through XV the calcined impregnated silica/ alumina support was impregnated with an aqueous solution of cobalt nitrate hexahydrate instead of nickel acetate. In each instance the mixtures were stirred thoroughly and then dried in an oven at 250 F., ground to a powder and then calcined for 2 hours at 1000 F. The details of these preparations are set forth in the following Table I in which the calculated chemical composition of the final catalyst, based upon the amount of ingredients employed in the preparation of the catalyst, also is given. The atom ratio of Mo/ Ni of each of Catalysts I through V and VIII through X11 was 2.5, while that of Catalysts VI and VII were 1 and 5, respectively.

I-IYDROGENATION RUNS The relative effectiveness of each of the above-described catalysts to etiect hydrogenation was determined by using the same in a laboratory hydrogenation test unit using benzene as a typical test feed, the test operation being carried out at conversions well below equilibrium conditions in order to obtain an accurate comparison of the catalyst activities. In these tests, the reactor (8" long with /2" inner diameter) was charged with 1 to 5 grams of catalyst powder using glass wool as packing, and alundum as the preheat zone. The reactor was connected into the unit and a hydrogen-hydrogen sulfide gas mixture containing 2 mole percent hydrogen sulfide was passed through the reactor at a pressure of between about 310 and about 330 p.s.i.g. The temperature was then raised to about 750 F., and the reactor was held under these conditions for 1 to 1.5 hours while passing the ri /H 8 gas stream therethrough. At the start of each run, the H /H S stream was then allowed to pick up benzene, the mole percent of benzene in the H /H S stream being constant at 0.55. In testing each catalyst the flow rate of the Hg/HgS benzene mixture through the reactor was changed in order to obtain at least two different conversions for each catalyst in order to obtain a sufiicient number of conversion values for calculation of the hydrogenation rate constant at a definite tempera- 9 ture, i.e. at 750 F. expressed as k F, The value of k represents the efiiciency of the catalyst to hydrogenate benzene to saturated liquid product at standard conditions of about 325 p.s.i.g. and 750 F. in the above-described system, and it relates to space velocity and conversion. The k value was then converted to the space velocity required to obtain a 90 percent conversion of benzene under these test conditions. It should be borne in mind that in this test operation the contact time in each instance was very low due to the fact that only a small quanity of catalyst was employed. This was done in order to operate Well below equilibrium conditions and thus obtain accurate comparisons. In each instance, however, at higher contact times, i.e. in the presence of more catalyst, the conversion of benzene in each instance is proportionately higher, but the activity of the catalyst remains the same. The specific test conditions employed and results of these runs are set forth in the following Table II.

CATALYST XVI A solution of 3.46 grams of phosphomolybdic acid hydrate, H PMo 0 -H O (72.69% M00 and 1.72 grams of nickel acetate tetrahydrate dissolved in 30 cc. of distilled water was added to 21.96 grams of gammaalumina analyzing 99 percent A1 0 0.02 percent S10 0.06 percent Na O and 0.03 percent Fe O After the mixture was stirred thoroughly, the excess water was removed by evaporation. The mixture was then dried at TABLE II Hydrogenation of benzene Run No 1 2 4 5 6 Catalyst No I XIII III XIV V XV Composition:

Percent M003. 3. 0 3.0 7. 6 7. 6 15.1 15.1 Percent NiO 0.6 1. 6 3.1 Percent 000 0. 6 1.6 3.1 pp 0) Pretreatment of Catalyst:

Catalyst charge, grams. 1. 0 1. 0 1. 0 1. 0 2.0 5.0 Catalyst Temperature,

F 750 750 750 750 750 750 Reaction Pressure,

p.s.i.g 324 325 325 325 313 329 Gas Composition Treatment time, hours 1 1 1 1 1.0 1. 6 Test Conditions:

Catalyst Temperature,

F 750 750 750 750 750 750 Reaction Pressure,

63 90 8 134 132 82 143 80 113 144 137 75 103 141 (i) R t Conversion, percent- 19. 9 15. 5 9. 3 5. 9 24. 6 31. 8 13. 5 14. 8 12. 6 10.7 56 32. 2 24. 4 Hydrogenation activity constant la F 14. 2 7. 8 37. 5 14. 4 36 8 Space velocity required to obtain 90% conversion of benzene 0. 0034 0. 0019 0. 0089 0. 0034 0. 0085 0. 0019 1 13 weight percent alumina/silica. 2 2 mole percent 1128 in H2. 3 Benzene.

From the data of Table II, it is apparent that the catalysts of this invention containing compounds of nickel and molybdenum on alumina/ silica possess significantly higher hydrogenation activity than the catalysts containing compounds of cobalt and molybdenum on the same support at substantially the same concentration of such compounds as tested under substantially the same operating conditions. The superiority of the nickel-containing catalysts is particularly marked at concentrations of molybdenum oxide of at least 7.6 as seen by comparison of the activity constant of Catalysts HI and XTV employed in runs 3 and 4, respectively, and of Catalysts V and XV employed in runs 5 and 6, respectively. It also is noteworthy that when the concentration of molybenum compound is increased in the cobalt-containing catalyst from 7.6 (Catalyst XIV) to 15.1 (Catalyst XV), the activity of the catalyst decreases about 44 percent whereas the same increase of the molybdenum concentration of the nickel catalyst lowered the activity of the catalyst by only about 4 percent. This latter comparison is significant from the standpoint of demonstrating that the molybdenum-nickel catalysts are basically different 210 F. for 22 hours, ground to a powder and then calcined for 2 hours at 1000 F. The calculated composi tion of the finished catalyst, based upon ingredents, is 10.07 weight percent M00 2.07 weight percent NiO, 0.53 Weight percent H PO and 87.1 weight percent A1 0 the Mo/Ni atom ratio being 2.5.

CATALYST XVII A solution of 3.46 grams of phosphomolybdic acid hydrate, H PMo O -H O (72.69% M00 and 1.72 grams of nickel acetate tetrahydrate dissolved in 30 cc. of distilled water was added to 21.96 grains of eta-alumina analyzing 99.8 Weight percent A1 0 After the mixture was stirred thoroughly, the excess water was removed by evaporation. The mixture was then dried at 210 F. for about 18 hours, ground to a powder and then calcined for 2 hours at 1000 F. The calculated composition of the finished catalyst, based upon ingredients, is 10.07 Weight percent M00 2.07 Weight percent NiO, 0.53 weight percent H PO and 86.15 weight percent A1 0 the Mo/ Ni atom ratio being 2.5.

CATALY ST XV III To 18.5 grams of desiccant grade silica gel (99.9 Weight percent SiO which hade been calcined for 2 hours at ratios of 1 (Catalyst VI), 2.5 (Catalyst V) and (Catalyst VII). The specific operating conditions and results of these runs are given in the following Table IV.

1000 F. there was added a solution of 1.4 grams of am- 5 TABLE IV monium molybdate tetrahydrate in cc. of distilled Hydrogenation of benzene Water. The paste was mixed thoroughly and then dried in an oven at 250 F. for 18 hours. To the dried solid Run N0 12 13 14 there Was then ad d additi na amoun f '1 ueous I an o I t 0 Catalyst No v1 v v11 solution of ammonium molybdate tetrahydrate solution, 10 0.824 gram of (NBLQ MO O -I-I O in water to Wet the Composition solid thoroughly. This mixture Was then dried in an ercen 1 03 15.0 15.1 15.0 oven at 250 F, for about 18 hours, followed by calcina- ,5 5 '2 tron for 2 hours at 1000 F. The calcined composite Support (1) (9 Pretreatment of Catalyst: (20.16 grams) was then impregnated with an aqueous Catalysteharge,grarnS 5.0 2.0 5.0 solution containing 1.27 grams of nickel acetate tetra- 750 750 750 hydrate to give a homogeneous paste which was then dried Reaction Pressure, 320 m 321 at 250 F., followed by calcihation for 2 hours at 1000 b g55g{ 15; (2) E (2) F. The calculated compos1t1on, based upon ingredients, fii gfiggg L0 was 9.01 Weight percent M00 1.87 weight percent NiO ctgtii lyst Temperature,

- s t 750 750 750 and 89.1 weight percent S10 the Mo/Ni atom ratio Reaction Pressure, b np.s.i.g.t 1 .H- 320 314 321 Catalysts XVI, XVII and XVIII Were tested as hydro- 174 235 137 75 119 157 206 genation catalysts using substantially the same test pro- 25 ggig (2g cedure and operating conditions employed in carrying out Resrgts: i t 5 v onvers on, percen 61.5 48.4 4 56 60.2 45.7 36.3 the above-described runs 1 through 6 of Tabie II. The Hydrogenation activity specific operating conditions and results obtained are set cmlstam w 36 Space velocity required forth 1n the following Table III which also sets forth, for to obtain a 90% conthe purpose of comparison, the results obtained with the 0-0077 0-0085 0-0049 above-described Catalysts IV and X which were prepared 11 h from the low and high alumina/silica supports, rei ggig fifiggt fi,3 5 32 spectively. Benzene- TABLE III Hydrogenation of benzene Run Nm 7 8 9 10 11 Catalyst No. XVI XVII XVIII N X COIIIDOSItIOtPlIH O 10 1 Percen 'o a i 10.1 9.0 10.1. 7. Percent NiO 2.1 h 2.1 1.9 2.1 1.2 Support Gam a-8 1 51 Etaalumina Silica 13% alumina/silica 25% alumina/silica Pretreatment of Catalyst:

Catalyst charge, grams 1.0 1. 0 5. 0 1.0 1.0 Catalyst Temperature, F 750 750 750 750 750 Reaction Pressure, p.s.1.v 325 325 330 325 325 Gas Composition Treatment time, hours 1 1 1, 5 1 1 Test Conditions: 750 750 750 750 750 Catalyst Temperature. Reaction Pressure, p.s.i.g. 325 325 322 325 325 Flow rate, standard con/mm. 113 81 43 29 131 2 1 21 1 120 1 2 20 Feed 2 R 1gllztirrier Gas (0 (0 0) CS S1 Conversion. percent 6. 0 7. 8 0 8. 2 14. 0 11 13 20. 4 21. 7 30. 2 34. 8 23. 7 17. 3 Hydrogenation activity constant [1 0 F- 6- 5 9.1 4. 6 54.7 45. 5 Space velocity required to obtain 00% conversion of benzene. 0.0015 0. 0022 (10011 0, 0130 0, 0108 1 2 mole percent 11 8 in H2. 2 Benzene.

From he t of T l 1 above, it y be e n h From the results shown in Table IV, it is apparent that the catalysts of this invention, e.g. Catalyst IV employed atom ratios f Mo/Ni f 1 d 2 5 i ld u r in run No. 10, and Catalyst X employed in run No. 11, possessed outstanding activity for the hydrogenation of benzene as compared with the alumina supported Catalysts XVI and XVII, employed in runs 7 and 8, respectively, and the silica-supported Catalyst XVIII, employed in run 9. a

The above Catalysts V, VI and VII, prepared as described in Table I above, were tested under the conditions set forth in the following Table IV using substantially the same test procedure described above in carrying out the runs or". Tables II and III. These runs Were made in order to test the effect oi": varying the atom ratio or" Mo/Ni at a constant concentration of molybdenum oxide. That is, each of these catalysts contained 15.1 weight percent M00 with varying amounts of N16 to provide Mo/Ni drogenation catalysts as compared with the catalyst in Which'the ratio was 5.

As indicated hereinabove, the low and high alumina/silica supports employed as the carrier for the,

TABLE V Hydrogenation of benzene Run No 15 16 17 18 19 Catalyst No I IX II III X Composition:

Percent M 3.0 3. 0 6 0 7. 6 7. 6 Percent NiO 0.6 0.6 1 2 1.6 1.6 Alumina/Silica Support, Weight Percent Alumina, based on support 13 25 l3 13 25 Pretreatment of Catalyst:

Catalyst charge, grams 1.0 1.0 2 0 1. 0 1 0 Catalyst Temperature, F. 750 750 750 750 750 Reaction Pressure, p.s.i.g 324 325 330 325 325 Gas Composition (1) Treatment time, hours 1. 0 1. 0 1 0 1.0 1 0 Test Conditions:

Catalyst Temperature, F 750 750 750 750 750 Reaction Pressure, p.s.i.g 324 325 334 325 325 Flow rate, standard (re/min. 63 112 163 120 95 132 82 143 120 162 206 Fe d R G imme G85 (U esu s: Conversion, percent 19. 9 15. 5 17. 3 12. 9 27. 7 34. 4 24. 6 31. 8 13. 5 34.8 23. 7 17.3

Hydrogenation activity constant [c 14. 0 37. 5 45. 5 Space velocity required to obtain 90% conversion of benzene 0.0034 0.0053 0.0043 0.0089 0.0108

Run No 21 22 23 24 Catalyst No IV V XI VIII XII Composition:

Percent M00 10.1 15. 1 15. 1 30. 2 2 Percent N10 2.1 3.1 3.1 6. 3 6 4 Alumina/Silica Support, Weight percent Alumina, based on support 13 13 25 13 25 Pretreatment of Catalyst:

Catalyst charge, grams 1.0 2 0 1 0 5.0 5 0 Catalyst Temperature, F 750 750 750 750 750 Reaction Pressure, p.s.i.g 325 313 325 320 330 Gas Composition Treatment time, hours 1. 0 1 0 1. 0 1. 0 1 0 Test Conditions:

Catalyst Temperature, F 750 750 750 p 750 750 Reaction Pressure, p.s.i.g 325 314 325 320 330 Flow rate, standard cc./min 161 218 261 137 75 150 183 107 66.0 144 172 193 Feed R Cfin'rier Gas esu s:

Conversion, percent 30. 2 21. 7 20. 4 56 35. 6 28. 6 63. 0 75 62.3 55. 4 51. 9 Hydrogenation activity constant km F. 54. 7 36 64. 8 19. 5 28. 0 Space velocity required to obtain 90% conversion O. 1030 0. 0085 0. 0153 0. 0046 0. 0066 1 2 mole percent 11 8 in H3. 2 Benzene.

From the data of Table V, it is apparent that the catalysts of this invention, and particularly Catalysts III, IV, V, X, and XI, containing above 6 and less than 30 wveight percent molybcdnum oxide, exhibit outstanding hydrogenation activity. Generally speaking, at the same level of concentration of molybdenum and nickel catalytic agents, the catalysts prepared from the alumina/ silica support containing 25 Weight percent alumina exhibit higher hydrogenation activity than those prepared from the support containing about 13 weight percent 69 alumina, the highest hydrogenation activity being exhibited by Catalyst XI. 7

In each of the runs of Table V above, the support was a. fresh alumina/silica support having a relative cracking activity of about 1.5. In order to test the efi'ect prior to impregnation with the molybdenum and nickel 75 then calculated from the observed compounds. In each case the steam-treated alumina/ silica support was then impregnated with an aqueous solution of ammonium molybdate tetrahydrate, dried at 250 F. and then calcined for about 2 hours at 1000 F. The calcined composite was then impregnated with an aqueous solution of nickel acetate tetrahydrate, dried at about 250 F., followed by calcination for 2 hours at 1000" F. Each of these catalysts was then tested, using substantially the same tset procedure employed in'carrying out the previously described hydrogenation runs including preconditioning of the catalysts with a hydrogen stream containing 2 mole percent H 8 at about 750 F. and about 325 p.s.i.g. for 1 hour. In each case-benzene was used mole percent H 8 as the carrier gas, and the hydrogenation was conducted at about 750 F. and about 320 to 325 p.s.'i.g. at various flow rates of feed. The hydrogenation activity constant at 750 F. expressed as k was conversions. The results of these runs are given in the following Tables VI and VII, in which the results obtained with the corresponding catalyst prepared from the fresh low and high alumina/silica supports are also given for the purpose of comparison.

as the feed stock employing hydrogen containing 2 5 Composition:

1 5 TABLE VI Catalyst No I III V Run No 25 26 27 Composition:

Percent M003 3.0

' Percent NiO 0.6

Sup Result constant k1 14 Catalyst Ne Run No XXI 2s 29 so Composition:

Percent M003 3. Percent N i0.. 0.

Support Results: Hydrogenation activity constant la F 17 37. 44

Catalyst No XXII XXIII XXIV Run No 31 32 33 Composition:

Percent M003 Percent NiO. Support Results: Hydrogenation ac constant 16750 F 19 35 4O 1 Fresh 13% alumina/silica having a relative cracking activity oi 1.5.

2 13% alumina/silica treated with 100% steam at atmospheric pressure for 24 hours at 1200 13. having a relative cracking activity of 0.6.

3 13% alumina/silica treated with 100% steam at atmospheric pressure for 24 hours at 1400 F. having a relative cracking activity of 0.3.

TABLE VII Catalyst No IX X XI Run No 34 35 36 Percent M003 3.0 Percent NiOa... 0.6 upp constant ltm F 22 46 65 Catalyst N0 XXVI Run No 37 38 39 can Catalyst No XXIX Run N0 40 41 42 Composition:

Percent M003 3. Percent NiO. 0.

Suppo rt Results: Hydrogenation activity 1 Fresh 25% alumina/silica having a relative cracking activity of 1.5.

2 25% alumina/silica treated with 100% steam at atmospheric pressure for 24 hours at 1200 13. having a relative cracking activity of 0.5.

3 25% alumina/silica treated with 100% steam at atmospheric pressure for 24 hours at 1400 F. having a relative cracking activity of 0.3.

From the results of Table VI above it is apparent that steam treatment of the alumina/ silica support containing 13 weight percent alumina prior to impregnation with the molybdenum and nickel compounds did not appreciably affect the hydrogenation activity of the catalysts. in fact, the activity of the catalysts containing about 3 and about 15 weight percent molybdenum oxide was increased by decreasing the relative cracking activity of the support; for example, com-pare the results of run numbers 25, 23 and 31 and of run numbers 27, 30 and 33. On the other hand, the results of Table Vii demonstrate the fact that steam treatment at 1400 F. of the alumina/silica support containing 25 weight percent alumina appeared to have the effect of decreasing the hydrogenation activity especially at the higher level of molybdenum oxide concentration; for example, compare the results of runs 36, 39 and 42. Although the activity of Catalyst XXX, for example, was lower than Catalyst Xi prepared from a fresh support, it still represents an improved hydrogenation catalyst. This is apparentby comparison of the results obtained with a catalyst supported on a different type of cracking support, namely silica/zirconia, such as Catalyst XXXI which was prepared as follows:

CATALYST XXXI To 20.45 grams of silica/zirconia, containing 20 weight percent silica which had been treated with 20 percent steam at i200 F. for 17 hours, there was added a solution of 4.63 grams of ammonium molybdate tetrahydrate V in 25 cc. of distilled water. The resultant paste was mixed thoroughly and then dried at 250 F. for 19 hours. The dried solid was ground to a powderand then calcined at 1000 F. for 2 hours. The calcined composite (23.8 grams) was then impregnated with a solution of 2.53 grams of nickel acetate tetrahydrate in 20 cc. of distilled water. The resultant paste was then dried at 250 F. for 20.5 hours, followed by calcinaiion for 2 hours at 1000 F. The calculated composition, based upon ingredients, was 15.1 weight percent M00 3.1 Weight percent NiO, 16.4 weight percent Zr0 and 65.4 weight percent SiO Catalyst XXXI was then tested for hydrogenation activity under substantially the same conditions as employed in the above-described hydrogenation runs. That is, 5.0 grams of Catalyst XXXI were charged to the abovedescribed hydrogenation reactor and preconditioned with a hydrogen stream containing 2 mole percent H 5 at 750 F., 325 p.s.i.g., for 1 hour. The hydrogen-hydrogen sulfide stream was then allowed to pick up benzene and the H /H S/benzene stream containing 0.55 mole percent benzene was then passed into the reactor at flow rates of S6, 123 and 181 standard cc. per minute at a reaction temperature of 750 F. and a pressure of 325 p.s.i.g. These flow rates yielded conversions of 40.8, 28.8 and 20.9, respectively, which corresponds to a hydrogenation activity constant, expressed as 10 of 8.8, which value is significantly lower than the value of the hydrogenation activity constants of the catalysts of this invention.

The following Catalysts XXXII to XXXIV were prepared to test the effect of preparational changes of hydrogenation activity. These catalysts were also tested for hydrogenation activity using benzene as the typical feed stock and using substantially the same test procedure described above. The specific operating conditions and results are set forth in the following Table VIII, in which the results obtained with Catalyst III above is also given for the purpose of comparison.

CATALYST XXXII I To 68.18 grams of 13 percent alumina/silica there was added a solution of 6.96 grams of ammonium molybdate .tetrahydrate in 75 cc. of distilled water. After thorough mixing, the paste was dried at 250 F. for 20.5 hours. The dried solid was then impregnated with a solution of 3.87 grams of nickel acetate tetrahydrate in- 40 cc. of water. The mass was then stirred thoroughly, dried at 250 F. and then calcined for 2 hours at 1000 P. The calculated composition, based upon ingredients, is 7.55 weight percent M00 1.55 weight'percent NiO, 11.32 weight percent A1 9 and 79.07 weight percent SiO CATALYST XXXIII This catalyst was prepared in the same manner as described for Catalyst XXXI, except that the final calcination step was effected for 2 hours at 1200 F. instead of at 1000 F.

CATALYST XXXIV tion, based upon ingredients, was 7.55 Weight percent M 1.55 weight percent Nit), 0.4- weight percent T1 1 0 68 weight percent Si0 and 22.5 weight percent AI O.

Ca talysts XXXII to XXXIV were tested using substantially the same test procedure as employed for testing the other catalysts. The operating conditions and results of these inns are tabulated in the following Table VIII.

TABLE 18 the above-described catalysts in a laboratory hydrocracking test unit using alpha-methylnaphthalene as the typical test feed. In these tests, the reactor (8" long with /2" inner diameter) was charged with 2.5 to 10 grams of catalyst powder using glass wool as packing and alundum as the preheat Zone. The reactor was connected into the unit and a hydrogen-hydrogen sulfide gas mixture containing 2 mole percent hydrogen sulfide was passed through the reactor at a pressure of from 780 to 800 pounds per square inch gage. The temperature was then raised to 900 F. and was held under these conditions for l or 2 hours while passing the hydrogen-hydrogen sulfide stream therethrough. At the start of each run, the hydro gen carrier gas was then allowed to mix with alphamethylnaphthalene, in a mixing chamber at the inlet of the reactor. The alpha-methylnaphthalene was fed from a buret and Lapp pump. The products were passed out of'the reactor through a water-cooled condenser into a high-pressure receiver maintained at 0 C. in which the liquid product was collected. The liquid product was Weighed and distilled. Overhead, up to 400 temperature, was taken as the gasoline product and the bottoms was considered cycle oil. Exit gas was expanded VIII Hydrogenation of benzene Run No c. 43 44 45 45 Catalyst No III XXXII 1 XXXIII 2 XXXIV 1 Composition:

Percent M00 7. 6 7. 6 7. 6 7, 6 Percent N1O 1. 6 1.6 1.6 1, 6 upp rt Pretreatment 0! Catalyst:

Catalyst charge, grams 1.0 1.0 1.0 1.0 Catalyst Temperature, C F. 750 750 750 750 Reaction Pressure, p.s.i.g 325 325 325 325 Gas Composition (5) a Treatment time, hours 1.0 1.0 1. 0 1, 0 Test Conditions:

Catalyst Temperature, 91 1. 750 750 750 75g Reaction Pressure, p.s.i.g 325 325 325 325 Flow ratefstandard co./n1i.n 132 82 143 100 106 230 107 152 110 I 160 203 Feed (9) a (9) 0 Carrier as. Results:

Conversion, percent 24. 6 31. 8 13. 5 34. 0 22. 0 15. 9 30. 3 27. 3 40. 2 29. 2 18.0 Hydrogenation activity constant [c1 0 F 37. 5 37. 5 43. 7 56, 0 Space velocity required to obtain 90% conversion of benzene 0. 0089 0 0089 0. 0104 0, 0133 1 The silica/alumina support impregnated with ammonium molybdate was not calcined prior to impregnation with nickel acetate. 2 The silica/alumina support impregnated with ammonium molybdate was not calcined prior to impregnation with nickel acetate and the final calcination temperature was 1200 F.

3 The catalyst was prepared by co-imprcgnation of the silica/alumina support with phosphomolybdic acid and nickel acetate.

4 13% alumina/silica. 5 2 mole percent H 3 H1 H2. 6 Benzene.

From the results of Table Vlll above it is apparent that omission of the calcination step between the ammonium molybdate and nickel acetate impregnations yielded a catalyst, i.e. Catalyst XXXII, equivalent in activity to Catalyst Ill, in which the ammonium molybdate impregnated alumina/silica support was calcined prior to the addition of the nickel acetate solution. However, a final calcination of the catalyst at 1200 F. as in Catalyst XXXH, improved catalyst activity about 15 percent; for example, compare the results of run numbers 4-4 and 45. As apparent from run number 46, co-impregnation of the alumina/ silica support with a solution of phosphomolybdic acid and nickel acetate improved the activity of the catalyst markedly, i.e. from a hydrogenation activity (la a of 37.5 to 56.

The relative effectiveness of the catalysts of this invention as hydrocraclcing catalysts was determined by using through a regulator into a low temperature glass receiver maintained at 60 C. and was metered. Product gas was analyzed by mass spectrometry. The amount of carbon laydown on the catalyst was determined by combustion. Refractive index of the gasoline and cycle oil was used as a measure of the amount of hydrogenation. In these tests, the above described Catalysts LHI, VIII- XI, 7 XXVI, XXXIII and XXXIV were employed. For the purpose of comparison, a commercially available cobalt molybdate catalyst analyzing 13.8 weight percent M00 3.1 weight percent C00, 0.9 weight percent SiO and 82.2 weight percent A1 0 also was tested under substantially the same operating conditions; this latter catalyst is designated as Catalyst XXXV. The specific Operating conditions and results obtained in testing the catalysts of this invention as hydrocracking catalysts, are set forth in the following Table IX.

F. vapor 1% TABLE IX Hydrocracking tests Run No 1 2 Catalyst No I Composition:

Percent M Percent NiO.

Alumina/Silica Support,

Weight Percent Alumina Weight, grams Activation, 2 Mole Percent Temperature,

Gas rate, cu.

70 F Operating conditions:

Temperature, "F Pressure, p.s.i.g- Time, hours Space velocity, W.[hr./w. Gas/Oil, MJM Yields, Weight Percent Output:

G215 (C C- Gasoline Cycle Oil Carbon i. Conversion, Weight Percent (single pass) Product Inspections:

An p (Feed minus Gasoline) l0* An n (Feed minus Cycyle Oil) 10 Relative Hydrocracking Activity Carbon Producing Factor". Hydrogenation Activity Constant, kmr

Run No 7 8 9 Catalyst No XXXIV Composition:

Percent M00 Percent NiO Alumina /Silica Sup- 7 port, Weight Percent Alumina Weight, grams Activation, 2 Mole Percent HIS in 11 Temperature, F Pressure, p.s.i.g. Time, hours 1 1 1 1 1 Gas rate, cu. it./hr.

con:

Operating Conditions:

Temperature, 11-... Pressure, p.s.i.g Time, hours Space velocity, w./

hr./w Gas/Oil, M./M Yields, Weight Percent Output:

Gas (C1-C4) Conversion, W

cent (single pass) 32. 2 Product Inspections:

An n (Feed minus Gasoline Xl0 1, 208 An n (Feed minus Cycle Oil) 278 Relative Hydrocracking Activity Carbon Producing Factor. Hydrogenation Activity Constant, kr5o r 1 Alumina/silica support treated with 100% steam at atmospheric pressure for 24 hours to a relative cracking activity of 0.5.

2 The alumina/silica support impregnated with ammonium molybdate was not calcined prior to impregnation with nickel acetate and the final calcination temperature was 1200 F.

1 The catalyst was prepared by co-impregnation of the silica/alumina support with phosphomolybdlc acid and nickel acetate.

4 3.1% 000. 5 0.9% Si z/82.2% A1 0 The low hydrocracking activity and poor selectivity of the cobalt molybdatc catalyst, i.e. Catalyst XXXV cmploycd in run No. 12 of Table IX necessitated the adoption of the more active Catalyst III employed in run number 4 as the reference catalyst. The relative hydrocracking activity values set out in Table IX are defined asc the space velocity of the particular run divided by the space velocity at the same conversion level obtained with Catalyst III. The carbon producing factor is defined as the carbon yield obtained in the particular run divided by the carbon yield for Catalyst III at the same conversion level. 7

From the results of Table IX, it is apparent that an improved hydrocracking process is obtained by the use of the catalysts of the present invention which catalysts also possess high hydrogenation activity. For example, the hydrogenation activity of Catalyst 'XXV employed in run No. 12 was one-third that of Catalyst I and only about one-fifteenth as active as Catalyst III. Notwith. standing the fact that the hydrocracking activity of Catalyst XXXV was low, its tendency to produce carbon was excessive; for example, compare the carbon producing factor of 12 exhibited by Catalyst XXXV with the carbon producing factor of 1.0 obtained with Catalyst III. Thus, from the standpoint of catalyst life and yields of desired liquid product, a catalyst such as typically represented by Catalyst XXXV which possesses high tendency to produce carbon is undesirable for use in a hydrocraclcing process.

Although catalysts prepared from alumina/ silica containing 25 Weight percent alumina, such as Catalyst X, employed in run No. 8, exhibited relatively less hydrocracking activity and a somewhat greater tendency to produce carbon than the catalysts prepared from the low alumina/ silica support, it is to be noted that steam treatment of the 25 weight percent alumina/silica sup-' port greatly enhanced the activity of the catalyst and significantly increased its selectivity as evidenced by a lowering of the carbon producing factor; for example, compare the results obtained in runNo. 9, which employed the steam treated Catalyst XXVI With those. employed in run No. 8, prepared from the fresh 25 weight percent alumina/silica support. In this connection it is to be further noted that a similar steam treatment of the 13 weight percent alumina/ silica support tended to yield a catalyst of lower hydrocracking activity and selectivity than one prepared from the some support Whichwas not steam treated; for example, compare the results obtained in run No. 5 which employed Catalyst XX prepared from the steam treated support with run No. 4 which employed Catalyst III prepared from the fresh support.

As noted above, co-impregnation of the silica/ alumina support with phosphomolybdic acid and nickel acetate yielded a catalyst of improved hydrogenation activity as compared with one in which the support was impregnated successively with the respective precursors of the molybdenum and nickel catalytic agents. In regard to hydrocracking activity, the same increase in activity was also observed. This is demonstrated, for example, by comparing the relative hydrocracking activity (1.5) of Catalyst XXXIV employed in run umber 7 of Table IX with the relative hydrocracking activity (1.0) observed with Catalyst III employed in run number 4.

Further improvement in the hydrocracking activity of the catalysts of this invention is realized by incorporating therein a minor proportion of a compound of cobalt in an amount between about 0.2 and about 2.0 Weight percent based on the total weight of the catalyst. Such catalysts are typically represented by Catalyst XXXVI which was prepared as follows:

CATALY ST XXXVI To 22.53 grams of silica/ alumina containing 13 Weight percent alumina, there was added an aqueous solution of 2.3 grams of ammonium molybdate tetrahydrate in 35 cc. of distilled Water. The resultant paste was mixed thoroughly, excess water was evaporated, and was then dried in an oven at 250 F. for about 22.5 hours. The dried solid was then ground to a powder and calcined for 2 hours at 1000 F. The calcined composite (23.17 grams) was then impregnated with a solution containing 1.2 grams of nickel acetate tetrahydrate and 0.72 gram of cobalt nitrate hexahydrate in 25 cc. of distilled water. The resultant paste was then mixed thoroughly while excess water was evaporated and was dried in an oven at 250 F. for about 22 hours. The dried solid was then ground to a powder and calcined for 2 hours at 1000 F. The calculated composition, based upon ingredients added, was 7.55 weight percent M 1.55 weight percent NiO, 0.79 weight percent C00, 78.4 weight percent SiO and 11.7 weight percent A1 0 The hydrocracking activity and selectivity of Catalyst XXXVI was tested as described above for efiecting the hydrocracking tests of Table IX using alpha-methylnaphthalene as the feed and the above-described hydrocracking test procedure. The specific operating conditions employed are set forth in the following Table X, which also sets forth the results obtained with the above-described Catalyst III, which did not contain the cobalt oxide promoter.

TABLE X Hydrocrackmg of alpha-methyl naphthalene Bun No 13 14 Catalyst N0 XXXVI III Composition:

Percent M00 7. 6 7.6 Percent NiO. 1. 6 1. 6 Sercent; C00- O 0.8 O 0 uppor 1 1 Weight, grams 5.0 5.0 Activation, 2 Mole Percent 1128 Temperature, F 900 900 Pressure. p.s.i.g 800 800 Time, hours 1 1 Gas, rate, cu. ft./hr. 70 F O. 535 0.505 Operating Conditions:

Temperature, F- 900 900 Pressure, p.s.i.g. 800 800 Time, hours 2 2 Space velocity, w. 3. 65 2.13 Gas/Oil, MJM 5.83 9.8 Yields, Weight Percent Output:

Gas (C1-C4) 4. 1 7. 7 Gasoline 28 1 52 Cycle Oil 65. 2 38. 0 Carbon 2.6 1.8 Conversion, We 34. 8 62.0 Product Inspections:

Ann (Feed minus Gasoline) X10 1,191 1, 287 App (Feed minus Cycle Oil) X10 259 253 Relative Hydrocracking Activity 1. 5 l. 0 Carbon Producing Factor 1. 0 1.0

1 13 weight percent alumina/silica.

From the results of Table X, it is apparent that incorporation of a minor proportion of a promoter comprising .a compound of cobalt increased the relative hydrocracking activity from 1.0 to 1.5 or increased the hydrocracking activity of the catalyst by SOpercent. It is to be further noted that this improvement in hydrocracking activity was obtained without any adverse effect on the carbon producing factor.

CATALYST XXXVII To 45.45 grams of commercial magnesia/silica cracking catalyst containing 30 weight percent magnesia, there was added a solution of 4.6 grams of ammonium molybdate tetrahydrate in 40 cc. of distilled water. After mixing thoroughly, the paste was dried at 250 F. for 24 hours and was then calcined for 2 hours at 1000 F. To the calcined composite (45.72 grams), there was added a solution of 2.3 grams of nickel acetate tetrahydrate in a 45 cc. of distilled water. Excess water was then evaporated, the mixture was mixed thoroughly and was then dried at 250 F. for about 24.5 hours followed by calcination for 2 hours at 1000 F. The calculated composition of the final catalyst, based upon ingredients, was 7.55 weight percent M00 1.55 weight percent NiO, 27 Weight percent MgO, and 63 weight percent SiO CATALYST XXXVIII To 40.9 grams of comercial magnesia/silica cracking catalyst containing 30 weight percent magnesia, there was added a solution of 9.26 grams of ammonium molybdate tetrahydrate in 40 cc. of distilled water. After mixing thoroughly, the paste was dried at 250 F. for 22 hours, followed by calcination for 2 hours at 1000 F. To the calcined composite (45.8 grams), there was added a solution of 4.8 grams of nickel acetate tetrahydrate in 45 cc. of distilled water. Excess water was evaporated, and the mixture was then dried in an oven at 250 F. followed by calcination for 2 hours at 1000 F. The calculated composition, based upon ingredients, was 15.10 weight percent M00 3.10 weight percent NiO, 24 weight percent MgO and 57 weight percent SiO The silica/magnesia supported Catalysts XXXVII and XXXVIII were tested for hydrocracking activity and selectivity as described above for effecting the hydrocracking runs of Table IX, using alpha-methylnaphthalene as the feed and substantially the same test procedure. The specific operating conditions employed in these runs and results are tabulated in the following Table XI.

TABLE XI H ydrocrackzlzg of alpha-methyl naphthalene Run No 15 16 Catalyst No XXXVII XXXVIII Composition:

Percent M00 7.6 15.1

Igercent5 NiO;,. 1. 6 3.1

Weight, grams 10 10 Activation, 2 Mole Percent H S in H Temperature, F 900 900 Pressure, psi 800 800 Time, hours 1.66 1. 23

Gas rate, on. I 0. 67B 0. 653 Operating Conditions:

Temperature, F 900 900 Pressure, p.s.i.g 800 800 Time, hours 2 2 Space velocity, W./hr./w 1.03 1.07

Gas/Oil, M4901 10.0 9.5 Yields, Weight ercent Outp Gas (C1-C4) 4.2 4. 9

Gasoline 13.9 20. 9

Cycle Oil 79.0 70.8

Carbon 2.9 3. 4 Conversion, Weight Percent (single pass) 21.0 29. 2 Product Inspections:

Am) (Feed minus Gas0line) 10 1, 043 1, 111

Ann (Feed minus Cycle Oil) 10 166 146 Relative Hydrocrack'mg Activity 0.1 0.2 Carbon Producing Factor 14 9 hibited'a severe tendency to produce carbon, the carbon producing factors of these particular catalysts being of the same order as observed with the above cobalt/molybclate Catalyst XXXV employed in run number 12 of Table IX above.

From the above, it is apparent that the catalyst of this invention possess a particularly good combination of hydrogenation and cracking activity which renders them particularly useful for converting residual hydrocarbon oils, tars, waxes and other heavy materials remaining after lighter fractions such as those boiling within the gasoline boiling range have been removed from refinery process streams, to lower boiling and more useful hydrocarbon fractions. Because of their high hydrogenation activity, the products such as gasoline boiling range prod- Ali-J not, possess only a low degree olefinic unsaturation and thus do not necessarily have to be submitted to further hydrogenation before use.

When used as hydrocracking catalysts, the superior catalysts of this invention, are those containing from about 6 to about 20 weight per cent of the compound of molybdenum, the compound of nickel being present in an amount to provide an atom ratio of molybdenum to nickel of between about 1 and about 3, particularly between about 2 and about 3. When a low alumina/silica cracking base is employed, particularly active and selective catalysts are those containing the compound of molybdenum in an amount between about 6 and about 12 weight percent. When a high alumina/silica cracking base is employed, the superior catalysts are those containing from about 10 to about 20 weight percent of the compound of molybdenum; or catalysts in which the content of molybdenum compound ranges between about 6 and about 10 weight percent and in which the high alumina/silica support has been treated with steam at an elevated temperature such as between about 600 F. and about 1250 F. for a period of time between about 0.5 and about 48 hours.

Due to their low carbon producing tendency, the catalysts of this invention may be used for long periods of time without requiring regeneration or reactivation. -lowever, after the catalysts have become deactivated due to prolonged use, they may be regenerated by treatment with hydrogen at an elevated temperature to remove sulfur as hydrogen sulfide followed by treatment with oxygen or an oxygen-containing gas to burn off carbon, and then subjected to treatment with a hydrogen-hydrogen sulfide stream under the aforesaid conditions.

Various aterations and modifications of the hydrogenative processes, catalysts and methods of preparing the catalysts of this invention may become apparent to those skilled in the art Without departing from thescope of this invention.

Having described our invention, we claim:

A process for the destructive hydrogenation of a hydrocarbon fraction boiling above the gasoline boiling range which comprises treating a catalyst comprising nickel oxide and between about 6 and about 20 weight percent of molybdenum oxide, and between about 0.2 and about 2 weight percent of cobalt oxide supported on a silica/alumina carrier containing between about 10 and about 30 weight percent alumina, the atom ratio of molybdenum to nickel being between about 1 and about 3, with hydrogen sulfide at an elevated temperature, and contacting said hydrocarbon fraction with said catalyst in the presence of a hydrogen-rich gas at a temperature between about 600 F. and about 925 P. such that conversion of said hydrocarbon fraction to lower boiling normally liquid product is effected.

References Cited in the file of this patent UNITED STATES PATENTS 

